Electrical plug-type connections have a wide variety of uses. They make it possible to connect electrical devices or assemblies by manually joining together mutually complementary connection elements. In order that said elements can be joined together without a large amount of force being used, the required plug-in forces are designed to be as low as possible. However, this means that the contact force in such plug-type connections is lower than is the case in screw-type connections or clamping connections, for example.
A lower contact force in plug-type connections results in increased contact resistance at the contact point, at which a power loss is produced in the event of a current flow owing to the voltage drop. This results in heating at the contact point of the plug-type connection, which can result in accelerated contact degradation as a result of oxidation or a change to the structure of the contact materials used and ultimately in thermal destruction of the contacts.
A possible way of avoiding the disadvantages of excessive heating of the contact point consists in cooling of the plug-type connector. For example, the document US 2006/035488 specifies an air-cooled plug, which is intended to reduce the heating of the contact point. The plug has cooling laminates, which are thermally connected to the contacts. One disadvantage is the fact that the cooling laminates have a negative effect on the physical size of the plug and another is the fact that they make insulation of the plug more difficult.
Improved cooling of the contact point is achieved if the plug-type connection is cooled with a liquid coolant, e.g., water. The document EP 0 401 640 has disclosed such a liquid-cooled plug-type connection with complementary connection elements. During assembly, there is both an electrical connection and a coolant connection produced between the connection elements. The coolant connection exists, in the connected state, as a coolant line through the plug-type connection.
However, one disadvantage is the fact that the coolant channel is also opened, as well as the current path, when the plug-type connection is disconnected, with the result that the liquid coolant needs to be removed before the disconnection.